[1.16.5] Syncing player capabilities to client

[TheDerpyParagon]

I'm trying to sync player capabilities from server to client using packets. I've researched about this topic a lot, but man is it confusing. I'm trying to update the players data on the client side when the player logs in, respawns, and when they change dimension. I also do so with the event StartTracking. Here are those events:

 @SubscribeEvent
    public void onPlayerTracking(PlayerEvent.StartTracking event) {
    	
    	if(event.getTarget() instanceof PlayerEntity) {
    		PlayerEntity player = (PlayerEntity)event.getTarget();
    		ServerPlayerEntity target = (ServerPlayerEntity)event.getPlayer();
    		if(!player.getCommandSenderWorld().isClientSide()) {
    			player.getCapability(TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY).ifPresent(capability -> {
    				CompoundNBT nbt = new CompoundNBT();
    				Capability<ITitanShifters> cap = TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY;
    				Capability.IStorage<ITitanShifters> storage = cap.getStorage();
    				nbt.put(cap.getName(), storage.writeNBT(cap, capability, TitanShiftersMod.direction));
    				ClientMessage message = new ClientMessage(nbt);
    				TitanShiftersNetwork.CLIENTCHANNEL.send(PacketDistributor.PLAYER.with(() -> target), message);
    			});
    		}
    	}
    }
    
    @SubscribeEvent
    public void onPlayerLogin(PlayerLoggedInEvent event) {
    	ServerPlayerEntity player = (ServerPlayerEntity)event.getPlayer();
    	
    	if(!player.getCommandSenderWorld().isClientSide()) {
    		player.getCapability(TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY).ifPresent(capability -> {
    			CompoundNBT nbt = new CompoundNBT();
		    	Capability<ITitanShifters> cap = TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY;
				Capability.IStorage<ITitanShifters> storage = cap.getStorage();
				nbt.put(cap.getName(), storage.writeNBT(cap, capability, TitanShiftersMod.direction));
		    	ClientMessage message = new ClientMessage(nbt);
		    	TitanShiftersNetwork.CLIENTCHANNEL.send(PacketDistributor.PLAYER.with(() -> player), message);
    		});
    	}
    }
    
    @SubscribeEvent
    public void onPlayerRespawn(PlayerRespawnEvent event) {
    	ServerPlayerEntity player = (ServerPlayerEntity)event.getPlayer();
    	
    	if(!player.getCommandSenderWorld().isClientSide()) {
    		player.getCapability(TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY).ifPresent(capability -> {
    			CompoundNBT nbt = new CompoundNBT();
		    	Capability<ITitanShifters> cap = TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY;
				Capability.IStorage<ITitanShifters> storage = cap.getStorage();
				nbt.put(cap.getName(), storage.writeNBT(cap, capability, TitanShiftersMod.direction));
		    	ClientMessage message = new ClientMessage(nbt);
		    	TitanShiftersNetwork.CLIENTCHANNEL.send(PacketDistributor.PLAYER.with(() -> player), message);
    		});
    	}
    }
    
    @SubscribeEvent
    public void onPlayerChangeDimension(PlayerChangedDimensionEvent event) {
    	ServerPlayerEntity player = (ServerPlayerEntity)event.getPlayer();
    	
    	if(!player.getCommandSenderWorld().isClientSide()) {
    		player.getCapability(TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY).ifPresent(capability -> {
    			CompoundNBT nbt = new CompoundNBT();
		    	Capability<ITitanShifters> cap = TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY;
				Capability.IStorage<ITitanShifters> storage = cap.getStorage();
				nbt.put(cap.getName(), storage.writeNBT(cap, capability, TitanShiftersMod.direction));
		    	ClientMessage message = new ClientMessage(nbt);
		    	TitanShiftersNetwork.CLIENTCHANNEL.send(PacketDistributor.PLAYER.with(() -> player), message);
    		});
    	}
    }

Here is the packet I am sending:

public class ClientMessage {

	private CompoundNBT data;
	
	public ClientMessage(CompoundNBT d) {
		data = d;
	}
	
	public static void encode(ClientMessage message, PacketBuffer buffer) {
		buffer.writeNbt(message.data);
	}
	
	public static ClientMessage decode(PacketBuffer buffer) {
		return new ClientMessage(buffer.readNbt());
	}
	
	public static void handle(ClientMessage message, Supplier<NetworkEvent.Context> supplier) {
        NetworkEvent.Context context = supplier.get();
        context.enqueueWork(() -> {
        	
        	if(context.getDirection().getReceptionSide().isClient() && context.getDirection().getOriginationSide().isServer()) {
        		@SuppressWarnings("resource")
				ClientPlayerEntity p = Minecraft.getInstance().player;
        		
        		p.getEntity().getCapability(TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY).ifPresent(capability -> {
        			Capability.IStorage<ITitanShifters> storage = TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY.getStorage();
        			storage.readNBT(TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY, capability, TitanShiftersMod.direction, message.data);
        		});
        	}
        	
        });
        context.setPacketHandled(true);
	}

}

Here is my network class: (I made two networks for sending packets to server and to client)

public class TitanShiftersNetwork {
	
	private static int id = 0;
	
	public static final String NETWORK_VERSION = "0.1.0";
	
	private static ResourceLocation loc = new ResourceLocation(TitanShiftersMod.MOD_ID, "network");
	private static ResourceLocation Clientloc = new ResourceLocation(TitanShiftersMod.MOD_ID, "networkclient");
	
	public static final SimpleChannel CHANNEL = NetworkRegistry.newSimpleChannel(loc, () -> NETWORK_VERSION, version -> version.equals(NETWORK_VERSION), version -> version.equals(NETWORK_VERSION));
	
	public static final SimpleChannel CLIENTCHANNEL = NetworkRegistry.ChannelBuilder.named(Clientloc).clientAcceptedVersions(s -> Objects.equals(s, "1"))
			.serverAcceptedVersions(s -> Objects.equals(s, "1")).networkProtocolVersion(() -> "1").simpleChannel();
	
	public static void init() {
		
		CHANNEL.registerMessage(0, InputMessage.class, InputMessage::encode, InputMessage::decode, InputMessage::handle);
		CLIENTCHANNEL.messageBuilder(ClientMessage.class, id++).decoder(ClientMessage::decode).encoder(ClientMessage::encode).consumer(ClientMessage::handle).add();
		
	}
}

Here is where the Init() method is being called:

@SubscribeEvent
    public void commonSetup(final FMLCommonSetupEvent event) {
    	TitanShiftersNetwork.init();
    }

And here is where I am trying to update the data on the client side:

public static void InheritAttack(PlayerEntity player) {
		
		LazyOptional<ITitanShifters> titan = player.getCapability(TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY, TitanShiftersMod.direction);
		ITitanShifters titanShifter = titan.orElse(new TitanShifters());

		TitanShiftersStats.setAttackTitan(true, player);
		
		pureUnshift(player);
		
		System.out.println(player.getScoreboardName() + " is pure titan: " + titanShifter.getPureTitan().toString());
		
		ServerPlayerEntity p = (ServerPlayerEntity)player;
    	
    	if(!p.getCommandSenderWorld().isClientSide()) {
    		p.getCapability(TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY).ifPresent(capability -> {
    			CompoundNBT nbt = new CompoundNBT();
		    	Capability<ITitanShifters> cap = TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY;
				Capability.IStorage<ITitanShifters> storage = cap.getStorage();
				nbt.put(cap.getName(), storage.writeNBT(cap, capability, TitanShiftersMod.direction));
		    	ClientMessage message = new ClientMessage(nbt);
		    	TitanShiftersNetwork.CLIENTCHANNEL.send(PacketDistributor.TRACKING_ENTITY_AND_SELF.with(() -> p), message);
    		});
    	}
		
		System.out.println(player.getScoreboardName() + " has inherited the attack titan!");
	}

Rest of the code is here: https://github.com/TheDerpyParagon/TitanShiftersMod

Any help is much appreciated!

[warjort]

You need to explain what is not working. Nobody wants to look at some code and guess what might be wrong with it.

If you don't understand what is not working add some

log.info("I am doing this");
or
System.out.println("I am doing this");

to your code in relevant places. Then see if you can understand what is being not being done or is wrong from the log.

Even if you can't figure it out, it will let you ask a more focused question.

 

However: One thing that does look wrong is.

TitanShiftersNetwork.CLIENTCHANNEL.send(PacketDistributor.TRACKING_ENTITY_AND_SELF.with(() -> p), message);

From what I understand you only want to send to the player and not every player that is close by, which is what the above code does.

You don't have an entity id in your message, you are assuming the player only gets its own data.

As it stands, it will be overwriting player's data randomly from other players.

[Luis_ST]

8 hours ago, warjort said:

If you don't understand what is not working add some

log.info("I am doing this");
or
System.out.println("I am doing this");

to your code in relevant places. Then see if you can understand what is being not being done or is wrong from the log.

Even if you can't figure it out, it will let you ask a more focused question.

it is highly recommended to use the debugger of the IDE

8 hours ago, warjort said:

However: One thing that does look wrong is.

it depends on the usage of the Capability and where the data is used

13 hours ago, TheDerpyParagon said:

Rest of the code is here: https://github.com/TheDerpyParagon/TitanShiftersMod

i would recommend you to use a Git Client to upload files,
since the Git repo is missing existential data, so im not be able to clone your repo to debug this locally

[TheDerpyParagon]

9 hours ago, warjort said:

You need to explain what is not working. Nobody wants to look at some code and guess what might be wrong with it.

If you don't understand what is not working add some

log.info("I am doing this");
or
System.out.println("I am doing this");

to your code in relevant places. Then see if you can understand what is being not being done or is wrong from the log.

Even if you can't figure it out, it will let you ask a more focused question.

I tried to debug some of the points in the code where I need the client to get the NBT data from the server, and I figured out that none of them are working. For example, I tried to print out a line in the console with the StartTracking method:

@SubscribeEvent
    public void onPlayerTracking(PlayerEvent.StartTracking event) {
    	
    	if(event.getTarget() instanceof PlayerEntity) {
    		PlayerEntity player = (PlayerEntity)event.getTarget();
    		ServerPlayerEntity target = (ServerPlayerEntity)event.getPlayer();
    		if(!player.getCommandSenderWorld().isClientSide()) {
    			player.getCapability(TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY).ifPresent(capability -> {
    				CompoundNBT nbt = new CompoundNBT();
    				Capability<ITitanShifters> cap = TitanShiftersProvider.TITAN_SHIFTERS_CAPABILITY;
    				Capability.IStorage<ITitanShifters> storage = cap.getStorage();
    				nbt.put(cap.getName(), storage.writeNBT(cap, capability, TitanShiftersMod.direction));
    				ClientMessage message = new ClientMessage(nbt);
    				TitanShiftersNetwork.CLIENTCHANNEL.send(PacketDistributor.PLAYER.with(() -> target), message);
    				System.out.println("Tracking working!");
    			});
    		}
    	}
    }

Which didn't work. The line never got printed on any of the method I tried this on. I even got rid of the line where it checks if the player is in the server side, and that didn't work either. Maybe the player doesn't have the capability? The capability system has been working fine for me so far, however.

Quote

However: One thing that does look wrong is.

TitanShiftersNetwork.CLIENTCHANNEL.send(PacketDistributor.TRACKING_ENTITY_AND_SELF.with(() -> p), message);

From what I understand you only want to send to the player and not every player that is close by, which is what the above code does.

You don't have an entity id in your message, you are assuming the player only gets its own data.

As it stands, it will be overwriting player's data randomly from other players.

Could you please provide a suggestion for how to fix this? I know I have to add an entity id in my message, but could you explain a bit more?

Edited July 2, 2022 by TheDerpyParagon

[Luis_ST]

45 minutes ago, TheDerpyParagon said:

Which didn't work. The line never got printed on any of the method I tried this on. I even got rid of the line where it checks if the player is in the server side, and that didn't work either. Maybe the player doesn't have the capability? The capability system has been working fine for me so far, however.

as i can see you never add your Capability  to the player using AttachCapabilitiesEvent

45 minutes ago, TheDerpyParagon said:

Could you please provide a suggestion for how to fix this? I know I have to add an entity id in my message, but could you explain a bit more?

you can use PacketDistributor.PLAYER

[warjort]

Quote

Could you please provide a suggestion for how to fix this? I know I have to add an entity id in my message, but could you explain a bit more?

A player on the server is being tracked by other players nearby. e.g. when I jump in the air, the server sends a message to the tracking entities to tell them I jumped in the air.

Using TRACKING_ENTITY_AND_SELF means it sends your message to all these players and your player.

In your client code you do

ClientPlayerEntity p = Minecraft.getInstance().player;
p.getEntity().getCapability().etc

So if the client gets a message because it is tracking another player, it will update the data from the other player into your player.

Using PacketDistributor.PLAYER means it only sends to the player. You won't have to worry about getting data about other players on the client.

[warjort]

Quote

Which didn't work. The line never got printed on any of the method I tried this on. 

You are using @SubscribeEvent on the methods, do you have @EventBusSubscriber(bus = Bus.FORGE) on the class?

[warjort]

In this code you have

    public void onPlayerTracking(PlayerEvent.StartTracking event) {
    	
    	if(event.getTarget() instanceof PlayerEntity) {
    		PlayerEntity player = (PlayerEntity)event.getTarget();

This is meant for when you do want your capability sent to other players. i.e. other players tracking you will get a copy of the capability data.

The "target" is the new player that has just come into range of you.

[warjort]

BTW, this looks weird

player.getCommandSenderWorld()

Its not wrong, its just your processing has nothing to do with commands. Normally you would just use the public field

player.level

which is what that other function returns.

[Luis_ST]

11 minutes ago, warjort said:

You are using @SubscribeEvent on the methods, do you have @EventBusSubscriber(bus = Bus.FORGE) on the class?

the bus is not required you can just use the default value, you only need to set the mod id

4 minutes ago, warjort said:

BTW, this looks weird

the fact that there is SeverPlayer#getLevel which returns a ServerLevel makes the name even weirder😅

[TheDerpyParagon]

1 hour ago, Luis_ST said:

1 hour ago, TheDerpyParagon said:

Which didn't work. The line never got printed on any of the method I tried this on. I even got rid of the line where it checks if the player is in the server side, and that didn't work either. Maybe the player doesn't have the capability? The capability system has been working fine for me so far, however.

as i can see you never add your Capability  to the player using AttachCapabilitiesEvent

I attach my capability to the player in my main class:

@SubscribeEvent
    public static void onAttachCapabilities(AttachCapabilitiesEvent<Entity> event) {
    	if (event.getObject() instanceof PlayerEntity) {
    		event.addCapability(resourceLocation, new TitanShiftersProvider());
    	}
    }

 

[TheDerpyParagon]

54 minutes ago, warjort said:

Quote

Which didn't work. The line never got printed on any of the method I tried this on. 

You are using @SubscribeEvent on the methods, do you have @EventBusSubscriber(bus = Bus.FORGE) on the class?

Yes.

@Mod.EventBusSubscriber(modid = TitanShiftersMod.MOD_ID, bus = Bus.FORGE)
public class TitanTransformationControl {

@Mod.EventBusSubscriber(modid = TitanShiftersMod.MOD_ID, bus = Bus.FORGE)
public class EventHandler {

[TheDerpyParagon]

1 hour ago, warjort said:

In this code you have

    public void onPlayerTracking(PlayerEvent.StartTracking event) {
    	
    	if(event.getTarget() instanceof PlayerEntity) {
    		PlayerEntity player = (PlayerEntity)event.getTarget();

This is meant for when you do want your capability sent to other players. i.e. other players tracking you will get a copy of the capability data.

The "target" is the new player that has just come into range of you.

So would I even need PlayerEvent#StartTracking if I don't want other players data?

[warjort]

Probably not.

[TheDerpyParagon]

Alright, I've fixed the issue and everything seems to be working correctly, thanks!